1. Bell Ringer
Which law says when pressure increases, volume decreases?
What stays constant in Boyle’s Law?
Which law says when temperature increases, volume increases?
What stays constant in Charles’ Law?

2. Bell Ringer 9-19-13 Solid --> Liquid = _________
Liquid --> Gas = _________
Gas --> Liquid = _________
Liquid --> Solid = _________
Solid --> Gas = __________

3. Gas Behavior
Chapter 3 Section 3

4. Measuring Gases Recall: Volume- amount of space that matter occupies
Measured in cubic centimeters (cm3), liters (L), milliliters (mL), and other units

5. Measuring Gases Recall:
Temperature- measure of the average energy of the motion of particles in a substance
The particles within any substance are constantly moving.
Faster the particles move --> greater the energy and greater the temperature
Thermometer - “speedometer” for molecules
At room temp (20oC), the particles in a gas move at about 500 meters per second- twice the speed of a jet plane

6. Measuring Gases
Pressure- force of its outward push divided by the area of the walls of the container
Pressure is measured in units called pascals (Pa).
Pressure = force
area
Ex: Higher gas pressure in a basketball keeps it inflated

7. Laws:

8. 1. Pressure and Volume 1. Boyle’s Law- states that p. 86 Boyle's Law
when the pressure of a gas at constant temperature increases, the volume of the gas decreases.
When the pressure decreases, the volume increases.
Inverse relationship (opposites)
p. 86
Boyle's Law

9. Examples of Boyle’s Law
The bubbles exhaled by a scuba diver grow as the approach the surface of the ocean. (The pressure exerted by the weight of the water decreases with depth, so the volume of the bubbles increases as they rise.)
Deep sea fish die when brought to the surface. (The pressure decreases as the fish are brought to the surface, so the volume of gases in their bodies increases, and pops bladders, cells, and membranes).
Pushing in the plunger of a plugged-up syringe decreases the volume of air trapped under the plunger.

10. 2. Pressure and Temperature
Sand storm Illustration
Gas particles travel quickly and randomly
At constant volume (closed container)
Increasing temperature, increases pressure
Decreasing temperature, decreases pressure
Temp, pressure

11. 3. Temperature and volume
Charles’ Law states that
when the temperature of a gas increases at constant pressure, its volume increases.
When the temperature of a gas decreases at constant pressure, its volume decreases.
Balloon illustration in video
Hot Air Balloons

12. Examples of Charles’ Law
A football inflated inside and then taken outdoors on a winter day shrinks slightly.
A slightly underinflated rubber life raft left in bright sunlight swells up (Why shouldn't you overinflate your life raft when your ship goes down in tropical waters?)
The plunger on a turkey syringe thermometer pops out when the turkey is done (The volume of air trapped under the plunger increases when the temperature inside the turkey climbs).

13. Charles Temperature Volume
Boyle Pressure Volume

14. Video
Bill Nye - Phases of Matter - YouTube